For the purpose of the diagnosis and treatment of diseases using light, optical fiber light sources based on various types of lamps such as halogen, xenon, metal-halide, mercury, etc. that are generally well-known have been used.
Such lamps have been selected based on technical and economic considerations, as well as on considerations for the special medical purposes of the devices and on manufacturing demands.
However, a single lamp applied thereto has not provided an optimal method in a case where a complex operation that needs various lights of a wide range or of a selective wavelength band is required.
In such a case, the device developer depends on a lamp having a special function or uses a plurality of lamps at the same time, thus overcoming the weak points.
Especially, it is known that the observation of geometry, position, and color of a diagnostic region by white light is essential in addition to the observation of fluorescence generated from the diagnostic object by the excitation light irradiation in diagnosing diseases using fluorescence.
In order to develop devices for diagnosing diseases through fluorescence generated in the diagnostic region, researchers have solved such problems via respective various methods.
For example, Karl Storz GmbH & Co. KG (Germany) uses a D-light xenon lamp that is a light source manufactured by itself.
Such a lamp provides good conditions for the observation in the white light if it has bright successive spectrums in a visible light region.
However, it causes an excitation energy loss for the fluorescence observation in a short wavelength range of 350 to 550 nm.
Xillix Technologies Corp. (Canada) uses a mercury lamp in its Onco-LIFE device. As is well known in the art, it is advantageous in the fluorescence emission from the diagnostic region to use the excitation light due to strong light beams in a spectrum of a short wavelength range rather than the other light sources.
However, the bright line spectrums of the light emitted from such a lamp make it difficult to provide a normal observation for the diagnostic object under the white light condition.
A light source of LumaCare (USA) developed for the execution of photodynamic therapy (PDT) uses a halogen lamp.
In this case, since the light strength of spectrum in a short wavelength range is not large, it cannot provide sufficient light strength permissible for phototherapy.
Like this, in the case where the single lamp is applied to the light source device, it is difficult to provide optimal conditions that satisfy various demands for the diagnosis and therapy.
Korean Patent No. 10-0411631 discloses a light source device using two lamps to improve the illumination quality in a fluorescence diagnosis device.
In the above-mentioned light source device, two lamps composed of a halogen lamp and a mercury lamp are established and the incident light from the two lamps are irradiated in turn on the end of the input surface of a light guide depending on a foldable mirror.
That is, according to the positions of the mirror, the excitation light emitted from the mercury lamp or the white light emitted from the halogen lamp is irradiated onto the light guide incident surface.
However, such a light source device has drawbacks in that the volume of the light source device becomes larger as it includes a foldable mirror driving unit and a control block and unnecessary heat is generated from the driving unit.
Furthermore, if the mirror does not reach a position in a proper angle, the light amount reflected by the mirror becomes smaller.